Utility classes and Spokane v1.5

Made the command canceler class actually cancel everything.
Made the command starter also work with a pre-created object.
Made the collector arms move faster by providing a secondary P term that
scales the outputs based on error.
Added two whiskers to the drive base.
Made the shooter pitch motor have stall detection.
Added a WaitForTrigger command that will wait for a trigger to reach a
particular state before returning.
Added an OnboardDigital Trigger subclass that uses a digital input to
emulate a trigger
Added a StallableMotor utility class for motors that need stall
detection.
Canceling in-group commands

Made the command canceler work with in-group commands at the expense of
only working with commands that subtype CommandBase.
Debugging Levels

Began adding debugging levels.
OI Whiskers and Time Based Updates

Made the OI panel update based on time instead of loop counts.
Made the drive base's whiskers give feedback to the OI.
Diddlers, Collecting, and Shooter Pitch

Made the shooter pitch subsystem not use the Stallable Motor class.
Made the collector-shooter-load command not raise the shooter.
Changed whiskers to diddlers.
Tuned shooter pitch.
Diddler Control and Collector Arms

Changed the 5 disk autonomous slightly.
OI-Based control of the Diddler Drive.
Changed the control speeds of the collector arms.
Tuned some other constants.
Version bump to 1.51

Bumped version to 1.51: Spokane Regional - Whiskers, Debugging, Group
canceling, and Constants